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Objective To investigate the level of finger systolic blood pressure (FSBP) in healthy young adults. Methods A total of 28 healthy young adults were selected as the study subjects by convenient sampling method. The FSBP of the study subjects was detected at 30 and 10 ℃, and the FSBP index (Fi) was calculated. Results The FSBP of the study subjects at 30 and 10 ℃ were (102.0±16.5) and (104.4±15.2) mmHg, respectively. The FSBP in male group at 30 and 10 ℃ was (99.6±18.6) and (107.2±17.0) mmHg, respectively. The FSBP in female group at 30 and 10 ℃ was (104.4±13.9) and (101.5±2.8) mmHg, respectively. The results of factorial analysis showed that the interaction between gender and temperature on FSBP was statistically significant (P<0.05). FSBP in male group was higher at 10 than 30 ℃ (P<0.05) and higher than female group at 10 ℃ (P<0.05). There was no statistical significance for the main effect of gender, temperature, finger, or the interaction effect of gender and finger, temperature and finger for FSBP (all P>0.05). The average Fi of the study subjects was (98.0±16.6)%, with males and females having the average Fi of (100.7±20.7) % and (95.2±10.6) % respectively. The results of factorial analysis of variance showed that there was no significant difference on Fi in the main effect gender and fingers or the interaction effect between them(all P>0.05). Conclusion The FSBP test could be used as a detection method for assessing peripheral microcirculation function in Chinese population. However, further research is needed to establish reference ranges and influencing factors.
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Objective: To analyze the status of noise hazard in workplace of key industries in Guangdong Province. Methods: A total of 1 061 enterprises from 14 key industries in 21 prefecture-level cities in Guangdong Province were selected as the research subjects using stratified sampling method. The occupational health survey was carried out, and the noise intensity in the workplace was detected. Results: There were 12 606 workplaces and 5 570 work sites involved among 1 061 enterprises. The median and the 0-100th percentile value ［M (P0-P100)］ of noise intensity in workplace were 82.6 (46.5-112.6) dB(A), and 35.03% of the workplace exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in workplace were in the northern part of Guangdong and the stone processing industry respectively. The M (P0-P100) of noise intensity in the work sites was 83.7 (47.5-106.2) dB(A), and 36.00% of the work sites exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in work sites were in the Pearl River Delta region and the ferrous metal mining and dressing industry respectively. The rate of noise protection facilities setting was 66.45%, and the validity of personal protection was 61.73%. The occupational medical examination was performed in 73.24% of the research subjects, and 3.25% of the result was abnormal. The industry with the highest occupational medical examination rate was nonferrous metal smelting and rolling processing, and the industry with the highest abnormal rate of occupational medical examination was stone processing industry. Conclusion: Noise hazards in workplaces of key industries in Guangdong Province are relatively severe, necessitating strengthened supervision and management, noise control measures, and efforts to reduce noise exposure levels in workplaces and work sites.
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Background Wearing anti-vibration gloves is a simple and effective way to prevent hand-arm vibration disease. The requirements for vibration damping gloves are varied by types of operations exposed to vibration. Objective To study the vibration attenuation and dexterity of different types of protective gloves, and to provide reference for scientific wearing of vibration damping gloves for people working with vibration exposure. Methods Nine kinds of common protective gloves (A and B were dipping gloves; C, D, and E were rubber gloves; F and G were textile and fabric gloves; H was cotton gloves; I was leather gloves) used by workers exposed to vibration in 28 factories in Guangdong Province were selected as research objects by typical case sampling method, and the basic parameters of included protective gloves were investigated and measured. According to ISO 10819:2013, a glove vibration transmissibility (GVT) test system was used to detect the vibration transmissibility values and analyze vibration attenuation characteristics of the subjects wearing different protective gloves. The dexterity was tested by Minnesota Manual Dexterity Test. Pearson test was used to analyze the correlations among glove thickness, vibration transmissibility, dexterity score, and grip strength score. Results For rubber gloves (C, D, and E), the associated average adjusted vibration transmissibility at middle and low frequencies \begin{document}$ {\overline T _{\text{M}}} $\end{document} and average adjusted vibration transmissibility at high frequency \begin{document}$ {\overline T _{\text{H}}} $\end{document} were lower than those of other gloves (0.89-0.91 and 0.59-0.80 respectively), the vibration transmissibility values of 50-200 Hz frequency band was 0.81-0.97, and the vibration transmissibility values of 315-1250 Hz frequency band decreased with the increase of frequency (the minimum value was 0.13). For other types of gloves (A, B, F, G, H, and I), the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} were 0.95-0.98 and 1.03-1.11 respectively, the vibration transmissibility values of 50-200 Hz frequency band was 0.96-1.02, and the vibration transmissibility values of 400-1250 Hz frequency band increased (the maximum value was 1.29). The \begin{document}$ {\overline T _{\text{M}}} $\end{document}, \begin{document}$ {\overline T _{\text{H}}} $\end{document}, and vibration transmissibility values of 40-1250 Hz frequency band of rubber gloves with double-layer protective materials (C, D, and E) were significantly lower than those of gloves with single-layer protective materials. But the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} of gloves of other types with double-layer materials (F, H, and I) were still greater than 0.9 and 1.0 respectively. Compared with single-layer protective materials, the gloves of other types with double-layer materials showed no significant changes in the vibration transmissibility values of 25-200 frequency band (0.91-1.06), and an increase in the vibration transmissibility values of 250-630 Hz frequency band (the maximum value was 1.22). The dexterity scores and grip strength scores of dipping gloves (A and B) were the lowest. Rubber gloves C had the highest dexterity score and grip strength score. The thickness of protective gloves was negatively correlated with the vibration transmissibility values, and positively correlated with the dexterity score and the grip strength score (P < 0.05). The vibration transmissibility value was negatively correlated with the dexterity score and the grip strength score (P < 0.05). Conclusion Among the 9 kinds of gloves, cotton gloves and leather gloves have no damping effect. Rubber gloves have certain vibration reduction effect, and the vibration reduction effect on high frequency band is better than that on low frequency band. The thicker the damping material is, the better the damping effect is, but the less the dexterity is. Appropriate damping gloves should be selected according to actual vibration operations.
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Hypertension is a risk factor for cardiovascular diseases. Many studies have found that exercise training, including aerobic exercise, resistance exercise and combined aerobic and resistance exercise, is beneficial for hypertension control. This article reviews the effect of different types of exercise training on hypertension and its underlying mechanism.
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Blast phase myeloproliferative neoplasm (MPN-BP) represent a type of secondary acute leukemia and are associated with a poor patient prognosis worldwide. Currently, there is no standardized treatment regimen for MPN-BPs, and treatment remains a major clinical challenge. In recent years, significant progress has been made in understanding the biological mechanisms of MPNs, especially the abnormal activation of the JAK-STAT signaling pathway caused by driver gene mutations; this has opened up a new avenue in exploring the mechanism and treatment of MPN-BP. However, in terms of disease pathogenesis, MPN-BP are different from primary acute leukemia, and different therapeutic strategies for MPN-BP have also been investigated. This article focuses on the advances made in MPN-BP treatment.
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OBJECTIVE: To analyze the current status of occupational exposure to power frequency electromagnetic field in converter stations. METHODS: Eight converter stations with voltage levels of ±500 kV and ±800 kV within normal operation were selected as the research subjects using the typical sampling method. Power frequency electric field and power frequency magnetic field strengths were measured and calculated according to the GBZ/T 189.3-2018 Measurement of Physical Agents in Workplace--Part 3: Electric Field and Magnetic Field between 1 Hz and 100 kHz. The GBZ 2.2-2007 Occupational Exposure Limits for Hazardous Factors in the Workplace--Part 2: Physical Factors were used to evaluate whether the power frequency electric field strength exceeds the regulatory limit(the occupational exposure limit of power frequency electric field in 8 hours workplace is 5.000 kV/m). Meanwhile, the test results were evaluated according to the short-term occupational exposure limit of 50 Hz electric field and magnetic field recommended by the International Committee on Nonionizing Radiation Protection in 2010 that are 10.000 kV/m and 1 000.00 μT. RESULTS: The power frequency electric field and magnetic field strengths of 582 working environment detection points were measured. The median and 0-100 th percentile of power frequency electric field and power frequency magnetic field strength were 4.342(0.001-12.003) kV/m and 5.51(0.10-186.90) μT, respectively.The exceeding standard rate of power frequency electric field strength in converter station workplaces was 37.8%(220/582), which concentrated in 500 kV alternating current filter area and 500 kV alternating current field area. Among them, 5 detection points had power frequency electric field strength exceeding 10.000 kV/m. The magnetic flux density of all the detection points did not exceed 1 000.00 μT. The power frequency electric field strength in ultra-high voltage region was higher than that in high voltage region(P<0.01). There was no significant difference in power frequency magnetic field strength(P>0.05). There was no significant difference in power frequency electric field and magnetic field between rectifier stations and inverter stations(P>0.05). The 8 hours time weighted average(TWA) value of power frequency electric field strength of 8 converter station operators was 1.044-2.335 kV/m, which did not exceed the occupational exposure limit. CONCLUSION: The converter station operators might be exposed to excessive power frequency electric fields for a short time, but the 8 hours TWA value of the power frequency electric field meets the requirements of standards, and the power frequency magnetic field exposure strength also meets the requirements of the relevant standards.
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OBJECTIVE: To analyze the characteristics of noise hazard in a nuclear power station. METHODS: The workplaces and working posts which exposed to occupational noise from two 1 000 MW power units in one nuclear power station in Guangdong Province was selected as study subjects using the convenience sampling method. Occupational health survey, noise measurement in the workplace and personal noise dosage measurement were used to monitor noise exposure, and to analyze the characteristics of occupational noise in the nuclear power station. RESULTS: The noise sources of the nuclear power plant were mainly distributed in the nuclear island, conventional island, and peripheral workshops. A total of 237 points of noise intensity were measured in the workplace. The intensity of noise ranged from 66.0 to 99.6 dB(A). The noise intensity in 62.4%(148/237) of points was equal or greater than 80.0 dB(A) and 34.2%(81/237) equal or greater than 85.0 dB(A). The percentage of detection points with noise intensity was equal or greater than 85.0 dB(A) from low to high were nuclear island, conventional island, and peripheral workshops with 22.0%, 37.5% and 53.8% respectively(P<0.01). The personal noise intensity of three positions including inspectors of operation department, preparation and main engine positions of mechanical department exceeded the occupational exposure limit(OEL), and the percentage of positions whose noise intensity exceeded the OEL was 9.7%(3/31). CONCLUSION: High-intensity noise sources of the nuclear power plant are widely distributed in the workshop areas of nuclear island, conventional island, and peripheral workshops. The noise level of some positions exceeded the standards of noise intensity. The prevention and control measures of noise hazards in posts with excessive noise should be strengthened.
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OBJECTIVE: To investigate the prevalence and risk factors of multi-site work-related musculoskeletal disorders(WMSDs) among workers in the industry of electronic equipment manufacturing. METHODS: A total of 815 workers in three factories of electronic equipment manufacturing in Guangdong Province were selected as study subjects by convenience sampling. The prevalence of multi-site WMSDs in the past year was investigated using Musculoskeletal Disorders Investigating Questionnaire and the influencing factors were analyzed. RESULTS: The total prevalence of WMSDs was 69.4%(566/815). The prevalence of multi-site WMSDs was 54.5%(444/815), and the prevalence of one-site WMSDs was 15.0%(122/815). Multiple logistic regression showed that female workers had higher prevalence of multi-site WMSDs than males [odds radio(OR) and 95% confidence interval(CI): 1.59(1.12-2.26), P<0.05]. The prevalence of multi-site WMSDs in left-handed workers was lower than that of right-handed workers [OR(95% CI): 0.42(0.19-0.91), P<0.05]. The longer service of current position and the more neck forward movement, the higher prevalence of multi-site WMSDs [OR(95% CI) were 1.33(1.09-1.63) and 1.62(1.23-2.15), P<0.01]. The workers who had long-time sitting at work, adopted uncomfortable working posture, could decide when to work on their own, kept head down for a long time, or often bending wrists up/down had higher prevalence of multi-site WMSDs [OR(95% CI) were 1.41(1.16-1.73), 1.82(1.40-2.38), 1.79(1.16-2.75), 1.92(1.38-2.69) and 1.60(1.14-2.24), respectively, P<0.01]. The workers who could take turns with colleagues to finish work or had enough rest time had lower prevalence of multi-site WMSDs [OR(95% CI): 0.57(0.41-0.78) and 0.67(0.48-0.92), P<0.05]. The workers who worked >10 h per day had lower prevalence of multi-site WMSDs than those who worked ≤8 h per day [OR(95% CI): 0.57(0.37-0.87), P<0.05]. CONCLUSION: Multi-site WMSDs were more common than one-site WMSDs among workers in the industry of electronic equipment manufacturing, and the prevalence of multi-site WMSDs was high. The risk factors include personal factors, work organization and adverse ergonomic factors.
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OBJECTIVE: To investigate the effect of hand-transmitted vibration on the subjective symptoms of mine drilling workers. METHODS: A total of 117 mine drilling workers exposed to hand-transmitted vibration were selected as the exposure group, and 46 workers without hand-transmitted vibration exposure were selected as control group by judgment sampling method. The Occupational Epidemiology Questionnaire of Mine Drilling Workers was used to investigate their subjective symptoms. RESULTS: The prevalence of tinnitus, hearing loss, cough and sputum in the exposure group was higher than that in the control group(P<0.05). The occurrence rate of numbness, tingling, self-reported white fingers and cold hands in the exposure group was higher than that in the control group(P<0.05). The total rate of symptoms of hand in the exposure group was higher than that in the control group(38.5% vs 21.7%, P<0.05). The multivariate logistic regression analysis results indicated that hand-transmitted vibration exposure and service length were risk factors of abnormal hand symptoms(P<0.05). CONCLUSION: Occupational hand-transmitted vibration exposure can affect the hand subjective symptoms of mine drilling workers, and the length of service is a synergistic influencing factor.
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Objective To explore the clinical features and prognosis of different PML_RARα fusion gene isoforms in acute promyelocytic leukemia (APL). Methods The clinical data of 78 patients initially diagnosed with APL in Fujian Medical University Union Hospital from February 2013 to July 2016 were collected. The clinical features and prognosis of different PML_RARα fusion gene isoforms were analyzed. Results There were 32 females (41%) and 46 males (59%) in 78 patients, with a median age of 40 years old (13-68 years old). The most common PML_RARα fusion gene was L type (48.7%, 38/78), followed by S type (46.2%, 36/78) and V type (5.1%, 4/78). The patients with white blood cell count more than 10×109/L (high_risk) occurred mostly in S type (61.1%, 22/36), compared with V type and L type, and there were statistically different (χ 2 ＝ 7.683, P < 0.05). A total of 78 patients included 8 cases (10.2%) of combined CD34 positive, 17 cases (21.8%) of combined FLT3_ITD mutation, 12 cases (15.4%) of combined DNMT3A mutation and 9 cases (11.5%) of additional chromosomal abnormalities. There were no significant differences in CD34 positive, FLT3_ITD, DNMT3A, and the incidence of additional chromosomal abnormalities among the three different isoforms (P＞0.05). The most common occurrence of retinoic acid syndrome (RAS) during treatment was S type (21/36), while rare for L type and V type (χ2＝ 7.633, P< 0.05). There were no statistical differences in the complete remission (CR) rate and disease_free survival rate among the patients with different PML_RARα isoforms (P＞0.05). Conclusions The clinical characteristics of different PML_RARα fusion gene isoforms are different, including most_common L type, more_common V type and S type in high risk groups; complicated RAS is commonly found in S type during the treatment. And different isoforms have no effect on the CR and DFS rate.
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OBJECTIVE: To evaluate the interlaboratory comparison results of noise measuring instruments in the occupational hygiene technical service institutions. METHODS: The basic performance data, multi-frequency acoustic calibration measurement results and simulated workplace noise at fixed points of 60 noise measuring instruments were collected. The instruments were from 60 occupational health technical service institutions who participate in the inter-laboratory comparison study in noise measuring instruments. The results of the measurements were analyzed using quartile robust statistical technology and z score evaluation method.RESULTS: All 60 participating comparison noise measuring instruments were examined or calibrated, and 58 instruments(96.7%) were used within the term of validity of examination or calibration. The 58 instruments were tested by multi-frequency noise calibration measurement. The comparative passing rate of the instrument accuracy was 94.8%(55/58); and the linearity test passing rate was 87.9%(51/58). There were 59 instruments participated in the simulated workplace noise at fixed points. The z-score pass rate of the two comparison measurement points was 89.8%(53/58). A total of 57 enterprises participated all the instrument performance comparison tests, with a pass rate of 94.7%(54/57). CONCLUSION: Performance of noise measuring instruments from the occupational hygiene technical service institutions is generally good. However, there are a small number of instruments have poor accuracy and linearity, and there are measurement bias that require improvement.
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Objective To observe the vasodilation effect of extract of Jasminum samba (EJs), a kind of traditional Chinese medicine, on ex vivo rat thoracic aortic rings, and to investigate its mechanism. Methods On ex vivo aortic ring perfusion device, influence of EJs on contraction of the aorta induced by phenylephrine (PE) or potassium chloride (KCl) was observed. Influence of N-nitro-L-arginine-methylester ( L-NAME ), barium chloride ( BaCl2 ), glibenclamide ( Gli ) on vasodilating effect of EJs (0. 5, 1, 2, 4, 8 g·L-1 ) was detected. Effect of EJs on the contraction of calcium chloride (CaCl2 ) and PE in Ca2+-free medium was detected. [ Ca2+ ] i in vascular smooth muscle cells was determined by using laser scanning confocal microscope (LSCM). Results In blood vessels with intact endothelium, EJs concentration-dependently decreased PE- or KCl-induced vasoconstriction, the maximum dilating effect being (105. 0±3. 2)% and (78. 0±6. 5)% , respectively; L-NAME affected the vasodilatory effect of EJs on thoracic aorta rings ( P<0. 01), the maximum dilatory effect being (58. 0 ± 6. 9)% . BaCl2 and Gli had significant influence on vasodilation of EJs, and the contraction was obviously attenuated (P<0. 01), the maximum dilatory effect being (37. 0±5. 2)% and (78. 0±10. 0)% , respectively. EJs significantly inhibited contracting effect of PE on thoracic aorta rings in Ca2+-free medium (P<0. 01). The maximum contraction effect was (70. 0±6. 3)% . EJs inhibited CaCl2-induced vasoconstriction (0. 5-8 mmol·L-1 ), and vasoconstriction was decreased by (65. 0±3. 2)% . LSCM recorded that Fmax / F0 of 4 and 8 g·L-1 EJs was (2. 0±0. 2) and (1. 5±0. 2), respectively. Conclusion EJs exerted a dose-dependent vasodilating effect on rat isolated aorta rings. The mechanism might be related to promoting NO release, activating K+channels and decreasing the concentration of cytoplasmic Ca2+.
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AIM:To observe the functional expression of calcium-sensing receptor (CaSR) in the mouse em-bryonic stem cells (mESCs).METHODS:The expression and distribution of CaSR were detected by Western blotting and immunofluorescence observation in 129 mouse ES-D3 cells.The intracellular concentration of free calcium ([Ca2+]i) was determined by confocal laser scanning microscopy .The cell viability was analyzed by MTT assay and flow cytometry .RE-SULTS:CaSR protein was expressed in mESCs .Extracellular calcium or neomycin significantly increased the expression of CaSR and [Ca2+]i.Neomycin increased the cell viability , up-regulated the protein expression of p-ERK2.These effects of neomycin were inhibited by NPS2390.CONCLUSION:CaSR is expressed in mESCs .The activation of CaSR is involved in the proliferation of mESCs .
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@#Objective To study the intracellular calcium ([Ca2+ ]i) in myocardial cell of obesity rats induced by high-fat diet. Methods Male Sprague-Dawley (SD) rats were divided into obesity resistant (OR, n=15), normal (Nor, n=15) and obesity prone (OP, n=15) group after fed with high-fat diet for 10 weeks. Their body fat and serum lipids were measured. Myocardial cells were isolated with Langendorff perfusion and [Ca2+]i was measured with calcium indicator Fluo-3/AM and laser scanning confocal microscope after KCl depolarization and caffeine- induced. Results Compared with those in Nor and OR rats, the epididymal fat, perirenal fat, omental fat and body fat increased in OP rats (P<0.05), as well as the the level of total cholesterol, triglyceride and low density lipoprotein (P<0.05); the vary of [Ca2+]i elevation and restoration were lower (P<0.05). Conclusion The vary of [Ca2+ ]i elevation decreases in OP rats after KCl depolarization and caffeine-induced, that may associated with arrhythmia in obesity rats.